Ultra rapid printing telegraph



July 16, 1935, H. CHIREI-X El AL 2,008,273

ULTRA RAPID PRINTING TELEGRAPH Filed Sept. 1, 1933 s Sheets-Sheet 1 INVENTOR HENRI CHIREIX BY ugsqea GOUDET A S M-H V ATTORNEY H. CHIREIX El AL Filed Sept. 1, 1933 3 Sheets-Sheet 3 ULTRA RAPID PRINTING TELEGRAPH July 16, 1935.

INVENTORS HENRI CHIREIX HUGUES GOUDET AI'I'ORNEY Patented July16, 1935 UNITED STATES 'ULTRA RAPID PRINTING TELEGRAPH Hem-i Chireix and Hugues Goudet, Paris, France,

assignors to Compagnie Generale de Telegraphic Sans Fil., Paris, France, a corporation of France Application September 1, 1933, Serial No. 687,756 In France September 28, 1932 6 Claims.

The present invention is concerned with a printing telegraph useful in connection with telegraph cables and in radioelectric communication work. As a general rule, the present system is to be used in large traffic multiplex operation,

whereas where the traflic load-is small it can also be worked by the simplex method.

In carrying the present invention into practice, use is made of a special code in which each letter or signal is characterized by the simultaneous transmission, in the form of a dash of fixed length, of two currents of diiferent acoustic frequencies chosen from among a certain possible number, say, 10 to 12. It is combinations in pairs of two simple frequencies which characterize the signal, and not the duration or number of transmissions of currentas in the Morse code or the position of these transmissions in reference to an origin as in the Baudot system. It may be noted here that in order to obtain additional signals also simple frequencies may be used.

Hence, the signals are, as a matter of fact, characterized by transmissions of any desired fixed length of one or of two frequencies (simple or combined).

There shall be first set forth the principle underlying the design of a printing telegraph receiver. Indeed, the principle on which this receiver instrument is predicated is the same as in a typewriter and is as follows:

Each key of a keyboard is controlled or actuated by a lever doubly locked in the inoperative position by two pawls and held in addition by a cam against the action of a retractile spring. The said pawls mounted upon shafts are controlled by electromagnets actuated in response to selective circuits tuned to acoustic frequencies (audio) chosen for the code. 7

Thus, when a certain sign or signal characterized by the transmission of two simultaneous and definite frequencies comes in at the receiver, one and only one lever will have its pawls released by the operation of the corresponding electromagnets. At the same time a mechanism controlled by a non-selective current will clutch a motor which by causing the cam to turn will liberate the lever which in its turn will control the corresponding key of the keyboard and strike it. This mechanism will at the same time produce forward feed of the paper and then restore the assembly so as to make it ready for a fresh signal.

The signals corresponding to the transmission of a simple frequency give rise to a somewhat more special ratchet gear for the striking levers as shall be indicated more clearly in what follows.

One important feature of the invention resides in the use, for the object of controlling the various electromagnets, of grid equipped tubes based upon ionization for their operation, to be more precise, tubes known to those skilled in the art as 5 an ionized gas relay with a control electrode Whose working differs but very slightly from triodes operating with a very high vacuum. It will be remembered that in an ionization tube fitted with a grid, if the grid is relativelynegative and 10 if a positive D. C. potential even'of high value, say, v, is applied to the plate, the tube will not be flashed and the current consequently is of zero value. If then, even for a very short period of time, the grid is raised to a relatively positive po- 15 tential known as the starting or flashing potential the tube will be flashed and rendered luminescent; the plate current assumes a value only governed by the resistance of the external circuit and preserves this value up till the instant 20 when the plate current is cut off. If the signal has stopped in the grid when the plate circuit is remade the plate current will not be restored.

The time required for the cutting of the plate circuit, on the other hand, may be very short (of 25 an order of one thousandth of a second or even less) It can thus be understood how useful tubes of this kind are in the work here considered.

As a matter of fact, a signal even of extremely great brevity, say, lasting some thousandths of one second, for instance, will suffice to cause operation of a relay that is comparatively slow and requiring a rather strong current such as one of the currents actuating the above mentioned pawls. The cutting of the plate circuit for the restoring of the tube should occur only after the striking of letters. It follows from what precedes that if there are available at the receiving end a certain number of receivers of the same kind the same 4 could be connected successively by the agency of a distributor to the line and pick up on each the transmissions of a different telegraph channel, it being understood that at the sending end these different transmissions are also effected sequen- 45 tially in the different channels.

This invention will best be understood by referring to the accompanying drawings in which Fig. 1 is a perspective view of a mechanical arrangement associated with a schematic circuit 50 diagram.

Fig. 2 is a detailed showing of one of the lever arrangements shown by Fig. l.

Fig. 3 is a detailed showing ofanother modification of one of the levers. t

Fig. 4 is a circuit diagram of the relay arrangement.

' Fig. 5 is a detailed circuit diagram of two gas tubes and two corresponding relays.

Fig. 6 is a circuit diagram of an arrangement wherein a plurality of frequencies is produced by tube-type generators of variable frequencies.

Figure 1, to'explain the idea, shows at the instant of the striking of a letter the disposition of areceiver connected with a definite brush of the distributer l turning in synchronism with a similar distributor mounted at the sending end.

The musical (of) currents are fed through transformer 2 and across resistances 3 to selective circuits 4 each thereof being tuned to one of the possible frequencies of the combinations that are used.

ed between grid and filament of gaseous control tubes 5 equipped with grids.

The circuit scheme relates to tubes whose flashing grid potential would be slightly positive. If this is not so a biasing cell common to all of the tubes may keep the grids at a lower potential close to the starting or flashing potential. The plate circuits of these tubes each contain a relay 6 actuating directly 2. line of pawls mounted upon shafts as indicated at 1. The joint return is established by'the break 8 being in the form of an insulating sector upon the periphery of a rotating drum built of metal and with which two brushes are in frictional engagement. The part played by the said break 8 as has been pointed out is to suppress the ionization in the tubes 5 when relays have been actuated and the signal been struck. 9 finally denotes the joint plate battery.

Another tube l similar to tube 5, but responsive to no matter what frequencies actuates a clutch II to couple the motor [2 on shaft IS. The plate circuit of this tube itself is broken at H similarly as at 8 before being reconnected with cell 9.

The bars I carrying characters and mounted along a circular arc upon the pivoting axis or fulcrum are controlled by rodlets I I and I 8 and the levers I9 having recesses for the pawls 2|. Levers I9 are subjected to the action of springs 22, the cam 23 being integral with the spindle l3 restores the levers l9 upon each turn.

The said shaft l3 also controls by the intermediary'of a Maltese cross or Geneva stop-24 a whole transmission system 25 which by the agency of the cylinder 26 and friction shoe 21 causesthe forward feed of the paper 28 during the intervals between signals and after each striking.

The said cylinder by the intermediary of the transmission 29 causes also the feeding of the endless inking ribbon 30 constantly passing over the inker 3| 32 designates the paper magazine.

Figure 2 shows at (a) one of the levers I 9 in the restoring position and at (b) the same lever released by the displacement of the cam. 23 and the simultaneously raising of two pawls 2i and 2| controlled by the relays 6 and 6' corresponding to the two frequencies belonging to the transmitted signal and causing the striking of the corresponding sign.

Figure 3 shows finally a modification based should be released by the action of a signal of this frequency, but in the presence of only this frequency, that is to say, not combined with another frequency.

For this purpose the lever I9 is locked in a state of inoperation by a pawl 2| corresponding to the respective simple frequency and fitted also with pawls corresponding to other frequencies; these being free in the state of rest come to lock the lever I9 when one of the other frequencies is sent simultaneously.

It will be seen that by adjusting conveniently the displacement of the breaking points 8 and I4 and by choosing a suitable profile for the cam 23, conditions can be made so that operation of the pawls will happen prior to the release of the cam; the requisite energy for the electromagnets 6 for reason of this fact can be made considerably lower inasmuch as it is feasible to provide a certain amount. of play for the pawiat their supporting points or seats.

According to a modification, there may be obtained a printing telegraph which mechanically speaking is even more nearly like to the common embodiment of a typewriting machine.

Moreover. such telegraph receiver may be constructed by using a common typewriter, preferably electrically actuated, in which the energy used for printing each letter is delivered by an electric motor, without that such typewriter has to be modified and owing to the only addition of a special case containing as many printing relays as there are keys on the key board. In such a case, use may even be made of the changeover from letters to figures" or. to capital letters, as well as of the special key for shifting the carriage back.

Referring to Figure 1, by keeping the same electrical diagram, that is the same circuits and parts numbered I, 2, 3, 4, 5 and 6 (the distributor I is provided only if the transmission is to be made on the multiplex principle) instead of the relays such as 6 assuming a mechanical task, they are only provided with electrical contacts which are closed when the ionized gas valves 5 are flashed. Figure 4 shows the electrical disposition of the circuits closed by such contact. In this figure: (a) means contacts on the first of the relays 6; (b) means contacts on the second relay 6; (0) means contacts on the third relay etc. It is then visible that-the key actuating relays numbered I, 2, 3, l etc., on Figure 4; can only be actuated if two contacts pertaining to two different relays 8 of Figure l, have been actuated.

For instance, key 2 will be-actuated by. means of relay l0 when contacts (a) and (c), pertaining to the first and third relaysi of Figure 1, respectively, have been actuated. In this modification, valve lll is suppressed and the de-ionization of the ionized gas tubes 5 is effected through relay 43, the contacts of which normally close the plate circuit of these valves (battery 44) and open it only during the very short time corresponding to the stroke from one contact to the other, this operation accomplishing the function provided by the cutting-oil in B.

All relays of Figure 4 are actuated by means of the local battery V.

The operation is thus, evidently, the same as described in relation with Figure 1, contacts a, b, c, etcu. having the same function as the pawls. Thechassis may be shifted back, when desired, by means of a relay, such as shown in l to 42 for actuating the corresponding key of the machine.

'tial in quadrature with The changing-over from letters to figures and inversely, maybe effected as easily, by means of the transmission of a particular sign on one or the other of the additional frequencies, the said sign having, moreoverf any duration, as it has been said above amongst the essential points of the invention. These frequencies are, once more, received in units like 3-4, actuating ionized gas tubes 5. The only difference resides in the connection of the relays controlled by such circuits, which may be looked as shown on Figure 5, in which 5 are gas tubes and 6 the corresponding relays, one of which controls (e. g. mechanically) the corresponding key. It is easy to see, on the connections shown, that the flashing of one of the relays 6- automatically causes the cutting-off of the other, and that the said flashing remains unchanged, until it is destroyed -by a transmission acting on the other tube.

Thus, after a short transmission, the machine will remain either in the letters or on the figures position, as long as desired.

What shall now be described is the preferable arrangement at the sending end in case of multiplex work on 12 telegraphic channels.

The two simultaneous frequencies (or single frequency for single frequency signals) are produced by two tube-type generators of variable frequency I and II (Figure 6) which embody an invention of one of the applicants forming the object of the copending application Ser. No.

585,489, filed Jan. 8, 1932, by Henri Chireix et al.

One of the applications in question 'would consist of a generator of currents of variable frequency and controllable by means of a direct current and it has there been disclosed that when applying to a tube generator a reaction potenthe potential set up in its circuit, the reaction thus occasioned results in action upon the transmitted frequency.

Tube I connected to act as a wave generator in any desired circuit scheme known in the art, by way of one of the secondary windings of transformer 2 excites an output tube 3-. The transmitted frequency, on the other hand, may be controlled by the amount of the grid polari- -zation of tube 4 also excited by another one of the secondary'windings of transformer 2. The currents amplified by tube 4 are transmitted (fed) to tube 5, the reactance of inductance 6 being sufficiently low in value so that the currents will be substantially out of phase to an amount equal to 1r/2. The currents amplified by tube 5 are returned byway of the third one of the secondary windings oi transformer 2 in the oscillation generating circuit. When the tube 4 is completely blocked the frequency producedhasa well defined value, the latter varying in a substantially linear manner with the amplification of tube 4, the direction of. the variation (increase or decrease of frequency) being related with the sense of the dephased reaction 1r/2 and which may be either lagging or leading.

The biasing of the tube 4 startingfrom an. initial condition governed by the cell 1 is itself a function of the fall of potential across the terminals of the resistance 6, the said voltage .drop in turn being governed by the current flowing through the circuit constituted by the mass (ground) cell ID, the central rim of a distributer III, contacts ll of a transmitter with a punched band IV and associated resistances l2.

In the case of three upper contacts and a punched paper tape as indicated at l3, it is possible to obtain six values of current according to whether rl, r2, 1-3 are alone in circuit or whether supplementary combinations rl, T2 in parallel, M, 13 in parallel and r2, 13 in parallel are likewise used, there will thus be seven values of frequency assuming that the sponds to the position with all contacts opened. The three lower contacts control in the same manner the generator II the frequencies of which in whole or in part differ from the former.

The transformer l4 common to both tubes 3 works into and feeds directly the outgoing line.

Transmitter IV itself is preferably designed in accordance with an arrangement similar to that disclosed in the United States Patent No. 1,893,159.

It is started letter by letter by the agency of a control electromagnet I5 whose function is to clutch a motor on a cam which successively:

1. Raises movable contacts ll opposite fixed contacts so as to establish electrical connection wherever the paper is perforated.

2. Leaves the contacts in the make condition for an instant.

3. Releases the same.

4. Causes forward feed of paper tape a distance corresponding to a signal.

In order that the function may be accurate it is evidently necessary that the cam of the transmitter should be in a position such as described above in item 2 at the instant where connection is established by the central rim of the distributer III, and for this purpose it is necter should be energized a certain length of time before and for a duration sufiicient so as to enable it to do its work; it is for this object that the control circuit of this transmitter comprises the ground, cell I8, left rim of the distributer, the electromagnet I5 here concerned and the regulating resistance IS. The small device provided at l1 insures the stopping of the transmitter by the short circuiting of the relay in the absence of perforated tape in the transmitter. It will be understood that there are as many fixed brushes upon the two rims on the left of the distributer III as there are telegraph channels; in other words, transmitters such as indicated at IV, 12 in the example here chosen.

Heterodyne I and II, on the contrary, serve for all of the channels and for this purpose the point that is not grounded of resistances 8 is associated in an independent manner with all of the transmitters IV.

Synchronism between the distributors at the sending and at the receiving ends is insured by the very signals that are transmitted, and the length and the cadence thereof are fixed. For this purpose the outgoing distributer III is fitted with a third rim (on the right) which will cause the short circuiting of the transmission periodically in a way so as to mark the working times and the inoperative periods. The signals themselves may thus actuate directly .a phonic wheel at the incoming end.

It is to be noted that this represents a preferred embodiment of the invention which is capable of a great many modifications both at the outgoing as well as at the receiving end.

For instance, at the sending end it could be conceived that the perforated tape is made .to control directly the transmission or output of independent generators corresponding to deflnite frequencies just as it would be conceive arather great number of constructional modifications for the receiver equipment. The

first value correfeasible to embodiments hereinbefore disclosed both for the sending as well as the receiving ends nevertheless represent equipment that is sufficiently simplified considering the purpose for which it is intended.

Summarizing, the leading idea is to actuate successively by the agency of sequential signals of extremely short length and any desired fixed duration receiver apparatus that may be relatively slow in such a manner that although the transmissions in the line are consecutive, the operation of all of these receivers seems simultaneous.

This result which presents especially great advantages in the case of radio electric signalling is realized by the use of tubes with control grids known as an ionized gas relay with a control electrode in accordance with a mode of working resembling that of certain known circuit arrangements called trigger relays. It will be obvious that in this application it would be feasible to provide any equivalent relay of a trip or trigger type for the ionized gas relays.

Whenever multiplex transmission is not aimed at the equipment at the sending end may be restricted to variable frequency generators II and II, these being actuated by a simple keyboard type contactor to take the place of the transmitter IV. Contacts H are then effected manually by the pounding of the operator.

What we claim is:

1. A printing telegraph receiver for extrarapid signals each formed bymeans of at most two superimposed frequencies simultaneously sent during a time interval non-characteristic of the signal, said receiver comprising in combination: a type writing machine provided with type carrying means and means to actuate said type carrying means according to twin frequencies signals, said actuating means comprising two windings, each of them energized by means of a selective release relay acting under the effect of a predetermined frequency.

2. A printing telegraph receiver for extrarapid signals each formed by means of at most two superimposed frequencies simultaneously sent during a time interval non-characteristic of the signal, said receiver comprising in combination: a type writing machine provided with type carrying means and means to actuate said type carrying means according to twin frequencies signals, said actuating means comprising two windings, each of them energized by means of an ionized gas tube with control grid, the input circuits of each of said tubes being adapted to selectively receive energy of a predetermined frequency, and means toopen the output circuits of said tubes after the operation of the corresponding type carrying means.

31A printing telegraph receiver for extra-rapid signals each formed by means of at most two superimposed frequencies simultaneously sent during a time interval non-characteristic of the signal, said receiver comprising in combination: a type writing machine provided with type carrying means and means to lock the control system of each of said type carrying means, and means to actuate said type carrying means according relays for supplying current when a signal frequency impulse is applied to their input, this current being thereafter supplied even after the impulse has ceased, and means for interrupting the supply of current from the output of said relay.

4. A printing telegraph receiver for extrarapid signals each formed by means of at most two superimposed frequencies simultaneously sent during a time interval non-characteristic of the signal, said receiver comprising in combination: a type writing machine provided with type carrying means some of which are adapted to be actuated by means of only one frequency, means for locking the control means of these last type carriers and windings associated with said locking means, each of them energized by means of a selective release relay working under the efiect of a different frequency, one of said windings corresponding to a predetermined frequency and releasing the locking means of the control means of one type carrier, while the other windings lock the same control means, when they are excited.

5. A printing telegraph receiver for extra-rapid signals each formed by means of at most two superimposed frequencies simultaneously sent during a time interval non-characteristic of the signal, said receiver comprising in combination: a type writing machine provided with type carrying means and means to actuate said type carrying means according to twin frequencies signals, said actuating means comprising two windings, each of them energized by'means of a selective release relay acting under the effect of a predetermined frequency, the said windings controlling two series connected contacts in the circuit of one relay in the control system of one type-carrier. I

6. A printing telegraph receiver for extra-rapid signals each formed by means of at most two superimposed frequencies simultaneously sent during a time interval non-characteristic of the signal, said receiver comprising in combination: a type writing machine provided with type carrying means and means to actuate said type carrying means according to twin frequencies signals, said actuating means comprising two windings, each of them energized by means of a selective release relay each of said relays acting under the effect of a predetermined frequency, means to re-set the system to rest after the operation of each type-carrier and means to shift forward the paper and the ink tape of the typewriter, said shifting means being controlled by means of a non-selective relay energized by the received wave.

HENRI CHIREIX. HUGHES GOUDET. 

